Here's Apple's full explanation, provided to Business Insider by a representative:

"Our goal is to deliver the best experience for customers, which includes overall performance and prolonging the life of their devices. Lithium-ion batteries become less capable of supplying peak current demands when in cold conditions, have a low battery charge or as they age over time, which can result in the device unexpectedly shutting down to protect its electronic components.

"Last year we released a feature for iPhone 6, iPhone 6S and iPhone SE to smooth out the instantaneous peaks only when needed to prevent the device from unexpectedly shutting down during these conditions. We've now extended that feature to iPhone 7 with iOS 11.2, and plan to add support for other products in the future."

What Apple is suggesting to fix the problem without having to purchase a brand new phone – just buy a new battery. That way your phone can handle the amount of power the updated software needs from the new battery, which will ultimately stop it from shutting off randomly.

It’s not just older iPhones that have batteries with a specific lifespan, says Apple. All of the products are built with one making the unexpected powering down a common problem.

According to Apple, if you charge your battery every night then after three years you should look into getting a new one because its life could soon be limited.

Instead of spending all your money buying the latest version, just purchase a new battery.